Radon: guidance on protective measures for new dwellings

This report gives guidance for reducing the concentration of radon in new dwellings, hence reducing the risk to occupants of exposure to radon. It provides practical details on methods of protecting new dwellings. This 1999 edition of the report replaces guidance published in 1991 for Cornwall and Devon and revised in 1992 to include parts of Somerset, Derbyshire and Northamptonshire.
The principal changes over previous editions reflect greater knowledge of radon-prone areas and the advances made in developing practical costeffective protective measures. In addition, the development of the protective measures and the monitoring of their effectiveness has indicated that the general approach to radon protection should be reconsidered and should embody the findings of this research.
Radon is a colourless, odourless gas which is radioactive. It is formed where uranium and radium are present and can move through cracks and fissures in the subsoil, and so into the atmosphere or into spaces under and in dwellings (Figure 1). Where it occurs in high concentrations it can pose a risk to health. Whilst it is recognised that the air inside every house contains radon, some built in certain defined areas of the country might have unacceptably high concentrations unless precautions are taken. In the UK, the granite areas of South-West England are of principal concern, but high concentrations of radon are also found in some other parts of the country.
Requirement C2 of Schedule 1 of the Building Regulations 1991[1] for England and Wales states that: ‘Precautions shall be taken to avoid danger to health and safety caused by substances found on or in the ground to be covered by the building’. The Approved Document[2] states that: ‘The precise areas where measures should be taken to provide protection against radon are reviewed by the Department of the Environment, Transport and the Regions (DETR) in the light of advice from the National Radiological Protection Board as this becomes available’. The Approved Document refers to the present report for detailed guidance on where such protection is necessary and for construction details.
Although this report offers guidance in support of the Building Regulations for England and Wales, the technical solutions described are equally applicable for use in Northern Ireland, the Channel Islands and other countries where construction methods are similar to those in the UK. Guidance for Scotland, based on this report, is in preparation. No guidance is currently supplied for suspended timber ground floors in new dwellings. The DETR is sponsoring research into how this form of construction could provide adequate protection against radon and will publish the results in due course.
This guidance was not prepared for non-domestic buildings. However, protection from radon at work is specified in the Ionising Radiations Regulations 1985[3], legislation made under the Health and Safety at Work Act[4] administered by the Health and Safety Executive (HSE). The technical guidance contained in the present report may be of use to designers and builders of new structures whose form of construction and compartmentation is similar to housing and where the heating and ventilation regime is similar to that used in housing. This is likely to include small office buildings and primary schools. Further information is contained in the HSE/BRE guide Radon in the workplace.

The plastic methods of structural analysis by Neal

Site Management of Building Services Contractors

Managing building services contractors can prove to be a minefield. The most successful jobs will always be those where building site managers have first built teams focused on tackling issues that might cause adversarial attitudes later on and jeopardize the project. The author shows how a simple common management approach can improve site managers' competency in overseeing building services contractors, sub traders and specialists, and maximize the effectiveness of time spent on building services

ASCE CONGRESS 2010

Structures Engineering Design Manual

This Structures Engineering Design Manual has been prepared by Structures Engineering Section of Main Roads Western Australia to provide a guide to the design of bridges and associated structures within MRWA.
The Manual is intended to fill a gap not covered by either the Bridge Design Code or standard text books. The Bridge Design Code provides detail of design principles, loads and standards to which all bridges designed by, or for, MRWA must comply. It does not, however, cover the application of these principles. On the other hand, standard texts cover structural analysis and design theory and application, but few are specific to bridge design in accordance with Australian codes. This area of specific application is what this Manual is designed to address. It is intended to be complementary to the Bridge Design Code and standard texts, but does not repeat material they contain, making use instead of a comprehensive list of references.
The Manual is also complementary to the Procedures in the Structures Engineering Management System. There is some unavoidable overlap between the two, but in simple terms the Structures Engineering Design Manual presents HOW things are to be done, whereas the Procedures detail WHAT is to be done, by WHO and WHEN.
This Manual is also complementary to the Bridge Branch Design Information Manual. Again, there is some overlap between the two, but basically the Information Manual is more mandatory, and presents MRWA specific variations or conditions that apply to the HOW things are to be done, as outlined in this Manual.
Each Chapter of the Manual has been written by an experienced, senior design engineer, with subsequent review and comment by other staff. It is intended for use by all members of Structures Engineering, but should be particularly useful as a training aid for new members of staff. It was this “young, qualified, but inexperienced engineer” that was the “target audience” during production of the Manual.
It must be stressed that the Manual is not a “cookbook” that can be freely used by all. It assumes a sound knowledge of structural engineering principles, awareness of the appropriate Codes and Standards and some background in bridge engineering. It must only be used by qualified engineers with some knowledge of bridge design, and/or under the supervision of an engineer experienced in bridge design. Although every care has been taken in the preparation of the Manual, because of the lack of control over its application, NO RESPONSIBILITY WHATSOEVER is taken for its use.
It is intended that the Manual shall be a dynamic document, subject to continual review. The need for change may occur due to the development of improved methods of analysis, new construction techniques, revised design standards etc. The Manual is the responsibility of the Senior Engineer Structures. However, all proposals for change shall be submitted in the first instance to the Structures Design and Standards Engineer.
The Manual is a controlled document as described in the Structures Engineering Document Control Procedure. In particular, a record shall be kept of the issue of the Manual to ensure that modifications are circulated to all.

Asphalt Mix Design and performance

Premature flexible pavement distress became a major concern in Indiana. As a result, a study was conducted investigating the major underlying factors. Pavement sections were investigated based on a factorial study with four factors comprised of climate, truck traffic, pavement base type, and wheel path. The distresses evaluated were rutting, thermal cracking and stripping. All were evaluated agaist control sections with zero distress. The pavement condition of each section was determined. Laboratory tests of field samples included physical properties, dynamic creep and recompaction. Results of the study indicate that the Asphalt Institute mix design criteria identify an asphalt content that is too high. Inplace densities were found to be inadequate and a recommendation was made to use higher field compactive effort. The USAE Gyratory Testing Machine (GTM) was used in laboratory" studies to recompact bulk samples of mixtures. Good agreement was shown between GTM and in situ bulk density and air voids. Tests confirm that the in situ asphalt content was too high. Gap graded gradations were found to be prone to rutting. Benefit is shown in using dynamic modulus to evaluate mixtures. A statistical analysis method, discriminant analysis, was used to accurately predict mixture field performance using laboratory data.